Affiliation
American Association of Variable Star Observers (AAVSO)
Thu, 01/25/2018 - 18:51
Hi Everyone,
I want to be involved in observing the Sun but I do not have the tools to do so. Can anyone make some recommendations on what type of solar telescope might be good to purchase. I do have some monetary restrictions as it cannot cost anymore than $1500.00 and I would like it to be something I could use at the next Solar Eclipse in the United States.
I do own an optical telescope NextStar 6SE but would prefer a telescope devoted solely to solar observing.
Any help would be appreciated.
-JoDee Baker
BJMB
Hi,
Do you already have a good mount?
I use an 80mm skywatcher with a solar filter. It is a little less than $700. A pretty versitile telescope at f/7.5. I also have a Coronado 60mm H-alpha costing around $1500. I used them during the last eclipse. The Skywatcher with the white light filter is better at totality and general solar viewing, but the H-alpha gives nice views of prominences, filaments and granulation. I recommend getting the full set of C-Max eyepieces with the barlow for the Coronado.
I use both on an iOptron ZEQ25 which I believe is no longer in production, being replace with the CEM25 at a little higher price, about $950. Mine is very stable with good electronics I use 5 different scopes interchangeably on it. Up to an 8in SCT.
Duane D.
At the moment the only mount I have is for my existing optical telescope and I realy don't want to use that for any other telescope.
Thanks for the suggestions. I appreciate it.
Hi JoDee,
You could get a "white light" filter for your existing telescope and you'd be all set for fairly high resolution solar observing or photography in visible wavelengths. These usually take the form of aluminized Mylar or inconel-coated glass. Very good for sunspots (easy to see both umbra and penumbra) and the more obvious plage activity (especially when set off by limb darkening), but these won't show prominences, filaments, or typical flares.
For Hydrogen alpha, the best I've used to date have been the Lunt solar telescopes, but they could easily exceed your price limit. Ha scopes tend to range from 40mm to about 150mm in aperture, and the more costly ones show a narrower bandpass around the H-alpha peak. Some units are tuned by a tilt mechanism, while better units include a tunable etalon chamber that allows fine adjustment of the wavelength seen/imaged. In the Lunt line, these are called "pressure tuners" Lunt offers single- and double-stack systems that have either one or two etalon pressure tuners. A single stack scope has a bandpass of around 0.6-0.7A, while the double-stack systems tighten that up to around 0.4 to 0.5 Ang. In practice, single stack systems give a brighter image that yields brighter prominences, while double stack systems produce a slightly dimmer image with greater contrast across the solar disc.
I get to play with a Lunt 80mm 'single stack' H-alpha scope that we use on a Celestron AVX field tripod/mount. Very nice scope, but not mine; it belongs to the observatory where I work part-time.
The Lunt 50mm single stack would just fit into your budget, and if you ordered a 2nd dovetail for the Celestron mount you currently have, it should work fine swapping places with your 6" telescope.
I've looked through Coronado PST H-alpha 'scopes, which have a really cool built-in finder gizmo, but never seem to deliver the detail and contrast of the Lunts I've used (50mm, 60mm and 80mm). Others may report very different (better) experiences with the Coronado line, and I've only looked through their smaller 40mm PST's, so I'm not suggesting you eliminate them from consideration, though I have been underwhelmed by the 3-4 that I've used.
BTW: photography with either white light or H-alpha systems is pretty easy with a small digital "eyepiece" camera, like the ASI 120, and the mono version works perfectly well for either option. Shooting 20 - 30 seconds of video and then stacking the frames in Registax can yield some very sharp images.
A last option that I just learned of 5 minutes ago is that Lunt now offers spiffy-looking 8 x 32 solar binoculars they are calling SUNoculars, which are outfitted with glass (inconel) filters over the objectives, which could make a real nice pairing with a similar filter over your 6" optics -- a quick check with bino's could tell you if its a good day to get out the telescope for a closer look. These retail for $129US, and it appears that they're also available for $89 used. Who knew?
Clear skies,
Brad Vietje, VBPA
Newbury, VT
www.nkaf.org
Brad,
Thanks for the great info. I managed to borrow a Coronado PST 40 mm from the school I teach at to see if it may just be "enough" to start out with. Although, from the reviews I have read it probably won't be.
I am going to look into the Lunt scopes as you suggest. Maybe if I am lucky I can get the school to purchase one :)
Thanks!!
JoDee
Hi JoDee
If you buy a LUNT for solar viewing, please consider this one:
https://www.highpointscientific.com/lunt-solar-systems-60mm-ha-telescop…
The reason is that you can use the H -Alpha filter and then 'tilt' the scope in declination to count the groups and sunspots. Also, to get familiar with the Solar Section and observing perhaps read the Solar Observing Guide, https://www.aavso.org/solar-observing-guide
We would very much welcome you as an observer, so perhaps become familiar with the SunEntry program used to record your sunspot observations.
Rodney
Solar Section Chair